Immunology. Therapeutic manipulation of gut flora

In developed countries as many as two individuals in every thousand suffer from inflammatory bowel disease (ulcerative colitis and Crohn's disease). In his Perspective, Shanahan discusses a new therapeutic approach to treating these conditions in which bacteria normally found in the gut are engineered to produce the anti-inflammatory cytokine interleukin-10 and then are fed as probiotics to mice with these disorders (Steidler et al.).     

Immunity, inflammation, and allergy in the gut

The gut immune system has the challenge of responding to pathogens while remaining relatively unresponsive to food antigens and the commensal microflora. In the developed world, this ability appears to be breaking down, with chronic inflammatory diseases of the gut commonplace in the apparent absence of overt infections. In both mouse and man, mutations in genes that control innate immune recognition, adaptive immunity, and epithelial permeability are all associated with gut inflammation. This suggests that perturbing homeostasis between gut antigens and host immunity represents a critical determinant in the development of gut inflammation and allergy.